INVOLVE SQ - IS COMING

[oxforddickie]

Hi Q8

Really good questions.
In regard to our 12 db separation rule I do not have any external published work. It really came down to a question we at involve asked a year or two ago. In the 70's the holy grail was 20dB and in the digital era anything less than 100 dB is clearly inadequate. So we set up a test arrangement where we could control the actual separation and got a bunch of golden eared types and simply trialed them on an instant A/ B switch asking the question could they identify the the CD 100 dB source. The results got random at 12 dB. Really interesting stuff.

If you check out the Haas precedence curve you will also note that 12 db is the "magic" number on that curve. I suspect its all tied in with evolved (or intelligent designed- for our christian brethren) human perception.

I'm going to play 'Devils Advocate' again

I don't believe 12db is anywhere near enough. irrespective of the often quoted 'Haas P.C.'. The greater the seperation (to a point) enables images to appear more 'solid', especially when they are situated in one of the corner positions. Yet again, the perfect example of this is the kettle drum (rear right) on 'Space Experience'.

Get it right and this is a real head-turner.

So, i throw down the gauntlet, please try using 20db as the minimum figure. It's more than possible to achieve, SQ/II is capable of >30db,and supplies rock solid imagery and superb recreation of reverberation/space. You come across that yet? The better the decode, the greater the re-creation of natural reverb, etc, especially important for classical music

 

[chucky3042]

Hi Oxforddickie

You have made some good points and I understand that it is controversial about our 12 dB rule but our tests on some "golden ears" were interesting.

We are currently trialing separations between 20 - 40 dB and listening for any problems such as image shift/ pumping......so far so good. The final choice will be based on final sound not just numbers.

Regards

Chucky

 

[bmoura]

Aw, I really wanted one of those Quadrafile albums. I always assumed it would be the ultimate in test records. But you know what they say happens when you "assume"

I always wondered about the Quadrafile discs. Sorry to hear the final product didn't match the promise. Oh well.....

 

[roundhousequad]

could you run your source be it sq or qs through a 3 band like the QS D1 then select you decode method that way you could have one three band and have the best for both SQ QS

 

[chucky3042]

Hi Roundhousequad

The "special" unit we are doing for QQ members is switchable from SQ/QS. The only compromise is that the center channel output is only available for QS (OR involve).

Regards

Chucky

 

[Overture]

Hello all.

Well, one week after our first bash at it, we're going back to humbly present ourselves to RustiAndi for the next batch of critical analysis on the morrow.
I've tightened some screws, and added some glue here and there. We're tri-band, though you probably knew that already.
The numbers make a little bit more sense now. - Interestingly there wasn't much inherently wrong, though we did discover that the CBS test tone disc had a 10 degree phase issue in the encode.
I started using the mathematically accurate encoded test tone at Quadraphonic.info - very useful. Potentially impossible to get that sort of tightened maths from the original SQ recordings, but it helped to figure some stuff out.

Incidentally it sounds great. It sounds like an Involve version of SQ, that is to say that not everything in the recording will show up as pinpoint, corners because our method also reproduces the spatial information that is in the recordings.
It's very....inclusive. Everything still sounds where it needs to be, and where it was deliberately put, but the extra ambience comes out in the sound field rather than being dragged to the corners with the other instruments. This is in mine and Charlie's opinion of course, hence taking it to a third-party to utilise what I can only describe as a wet-dream of a reproduction setup.
I could lose hours in that listening cave just...well, listening.

I'll get some separation numbers from the extreme positions of the reproduction, but given that, mathematically speaking the detection is good, the separation will be as good as the encode, which means crosstalk will be reduced to either the limitation of the recording equipment, or the limitation of the reproduction equipment.

Anyway, the version is marked as V0.8, so we're on the home stretch we think. I'll try and report tomorrow afternoon, though I expect Rustiandi will beat me to it again - the man is fast.

~David.

 

[oxforddickie]

Just a couple of notes from someone who has climbed this mountain before:

1) The SQ tones that "were" available on Quadraphonic.info are not accurate in respect of the encode equation, even if they are accurate in respect to 'phase',

2) In reference to your statement: "It sounds like an Involve version of SQ, that is to say that not everything in the recording will show up as pinpoint, corners because our method also reproduces the spatial information that is in the recordings", i recognise this (been there, done that etc), and i'm guessing that you've possibly missed a "very" important part of the equation that allows the accurate spacial reproduction of instruments, etc.

 

[Overture]

Just a couple of notes from someone who has climbed this mountain before:

1) The SQ tones that "were" available on Quadraphonic.info are not accurate in respect of the encode equation, even if they are accurate in respect to 'phase',

It was phase that I was more concerned with in this case. Though if you'd care to explain what you mean by not accurate, or point out an alternative set of test tones, that would be useful. And they are still available at that quadraphonic.info, I got them only this week.

2) In reference to your statement: "It sounds like an Involve version of SQ, that is to say that not everything in the recording will show up as pinpoint, corners because our method also reproduces the spatial information that is in the recordings", i recognise this (been there, done that etc), and i'm guessing that you've possibly missed a "very" important part of the equation that allows the accurate spacial reproduction of instruments, etc.

I can assure you that we haven't overlooked any part of the equation. Charlie and I have been arguing the finer points of it since we started. This week however we actually finally came to agreement on the finer points of it. Turned out to simply be a matter of communication.
However, please feel free to bring up anything specific that you're concerned about. Spatial instruments are quite accurate, and we're now hearing those particular spatial instruments that you are likely referring to quite clearly and well defined, in fact that was the subject of today's listening session.

 

[oxforddickie]

In respect to the tone, i thought they had been removed to their inaccuracies. As to telling you, after what has gone before, i'm only willing to try and point you in the right direction. After all, you all 'believe' your better than me.

Again, the area of the equation if always over looked by those unaware of how SQ works.

That's all for now

 

[Overture]

In respect to the tone, i thought they had been removed to their inaccuracies. As to telling you, after what has gone before, i'm only willing to try and point you in the right direction. After all, you all 'believe' your better than me.

Again, the area of the equation if always over looked by those unaware of how SQ works.

That's all for now

I'm sorry you feel this way.
We've never believed or claimed to be better than you at all. In fact we haven't drawn any comparison to what you do, and we've never reviewed any of your work. Nor did you accept our offer of an evaluation sample.

Members of the QQ forum who have already purchased a unit are probably in a better position than either of us to compare or comment on any comparison between the two.

In short, we aren't concerned about your work and we wish you well in it.

That's all for now

~David

 

[oxforddickie]

I shall no longer give you any clues where your problems lie in regards to SQ decoding, and i ceriously hope you can produce something that at least matches a Tate 2 "In Every Respect", or people may not be too happy..

As to your "offer?", i saw no point in purchasing a unit with obvious issues (proof: as per your test results).

That's all

 

[ArmyOfQuad]

What about the Project 3 test record, is that one accurate?

 

[chucky3042]

Hi Oxforddickie

I think we are both interested in a similar end result and we both agree that with appropriate encode decode technology a 2 channel matrix system can achieve as good (we claim better ) results than the more bandwidth hungry "discrete formats". We understand you have suspicions on how we have achieved our tested and claimed results. I do look forwards to your comments (and all qq members) as it does force us to re examine and even test out system.

I am disappointed at your last comment:

i saw no point in purchasing a unit with obvious issues (proof: as per your test results).

Where you claim there are obvious issues in our test results (presumably in the - Reality Teck Involve Decoder - proper QS decoding? - test results-thread). I note in the 2220 views of this thread no one has pointed out any "obvious issues" in the test results - not even the great Oxforddickie.
Our very biased conclusions (conducted by an independent subcontract physicist -Max Van Dongen Bsc Physics- hons first class) was that the performance of the Surround Master was if anything superior to the Sansui QSD-1.

I fear that you are now throwing patches of mud in the hope some of it will stick......you know sow the seeds of doubt in peoples minds. You have no doubt done a great job in your decode work and one day I hope to have the privilege of hearing them but as David said we really have never made any comparisons to this forum and have no interest in doing so.

If you have serious reservations and wish to alert qq members of "obvious issues" may I suggest you list them in the - Reality Teck Involve Decoder - proper QS decoding? - test results- thread.

regards

Chucky

 

[chucky3042]

Hi Armyofquad

Sorry we have not got that one.

regards

Chucky

 

[Overture]

Actually we do have the Project 3 test disc (PCM transferred from the Vinyl) - Charlie has only ever seen it as an unlabelled CD so he wasn't aware of it.

I've been using the tones and the noise positioning quite a bit - I find the tones are good for calibrating the numbers while the noise gives a good indication of how the system reacts to music.

I haven't seen any phase problems with that disc.

~David

 

[ArmyOfQuad]

Ah, cool, good to know that's an accurate disc, I have both the SQ and QS versions of it.

 

[Soundfield]

Chucky –
No need to worry, I don't think there's any danger of any "mud sticking". I ‘m sure most of us have been greatly amused by the wonderfully cryptic nature of the 'help' offered to you here, especially the suggestion that you should seek out some great mystical truth of the quadraphonic ancients buried deep in the encoding equation (!) As to "sowing seeds of doubt", actually your open responses here have ensured that nothing could be further from the truth. As an engineer I am hugely impressed by the progress you have made in, and let's not forget this people, the Real Time decoding of SQ (which brings a whole order of magnitude of complexity over and above that faced by off line scripts) so quickly. I am particularly encouraged by the insight offered by David's observation that....

"Incidentally it sounds great. It sounds like an Involve version of SQ, that is to say that not everything in the recording will show up as pinpoint, corners because our method also reproduces the spatial information that is in the recordings.
It's very....inclusive. Everything still sounds where it needs to be, and where it was deliberately put, but the extra ambience comes out in the sound field rather than being dragged to the corners with the other instruments."

as I think that represents the crossing of a real threshold of both your understanding of the fundamental requirement and the actual achievement of it. Nothing could be less realistic than the artifice of pinpoint positioning where none is warranted - it's not something we experience in the real world (If I go to a concert and close my eyes I cannot more than vaguely locate individual instruments within an orchestra many tens of metres away from me). But something remarkable happens to the overall acoustic focus when you get the context of the ambient environment right, sadly this is often for me where matrix systems have performed particularly poorly (at least in decode terms) compared to discrete systems.

I look forward to further analysis from Rustyandi. Keep up the good work.

 

[Q8]

My dream is that when this thing ships, I'll hook my turntable to it, I'll start auditioning SQ and QS records from my quad collection, and I will hear quad mixes with clear sound, the sound placed in the direction it was intended in the mix, at least with most records. Don't mind if there is a bit of ambience on top of that. My wish is that I may get to hear matrix recordings pretty much as they were originally purported to perform.

So far it sounds like this is what we will get.

 

[rustyandi]

1st the best way to listen to Quad is to have 4 of the same speakers
I have just heard the latest SQ decoder from Charlie
he has left it with me to play with
and I will
My first impression it is very[/B] good
I played a number of tracks switched from TATE to Surround Master SQ
while playing tracks the sound is very smooth the channels are very clearly define
I am not sure if it is better than the TATE or not yet
I love my TATE
But it is better than any logic decoder
All my reviews will be as a listener without any
Tec. background

 

[rustyandi]

Also if there is any body in the Melbourne area
that would like to listen to the unit
Let me know
As I would like to have a few views